main() {
  Map<String, String> person = {
    "name": "张三",
    "age": "18",
    "height": "1.80",
    "isStudent": "true",
  };
  print(person);
  //遍历person
  person.forEach((key, value) {
    print("key:" + key + " value:" + value);
  });
  //对person进行操作
  person["weight"] = "70";
  print(person);
  person.remove("age");
  print(person);
  person.clear();
  print(person);
  person["age"] = "20";
  print(person);

}
